Hi everyone, when powered on the macbook chimes and the screen is grey as usual but when it gets to where the folder logo has to appear (when no HDD is connected), then the screen starts flashing black and white. But when HDD is connected and it gets to the apple logo then the screen simply goes black (with backlight on).The macbook boots up fine and the screen works fine on another mac. Any help will be appreciated.

First see whether there is rust on the board near the connector by the LCD

There is no rust.

Its look like VGA problem

Problem was the screen cable. I swapped and it worked.